My arms, mainly left one seems to go numb only when I'm lying my back. What could cause this? Numbness is from shoulder blade to pinky and ring finger

Varies . The most common cause would probably be a pinched nerve in your neck. Other potential causes could potentially include thoracic outlet syndrome or one of multiple peripheral nerve entrapment syndromes such as carpal tunnel syndrome. I would not hesitate to be seen and a good exam could go a long way in determining the cause.
? pinched nerve. Although it usually occurs at a later age, these symptoms might be due to compression of nerve roots exiting the spine and serving the arms. A neurologist could clarify this with a careful history, physical exam and MRI of the spine.

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My doc is stumped after mri. I have severe pain in left shoulder that causes numbness in outter arm, pinky finger, and ring finger. I'm 26.

MRIs don't tell all. This needs more study it sounds like a radiating pain it might be in a net between your shoulder and neck or further down it could also be coming from an injury or trigger point in the muscle called the supraspinatus or even fibromyalgia doctor needs to look in more detail and possibly order an emg/ncv or other x rays. Read more...

I have severe pain in rt shoulder blade that radiates down my arm. At the elbow it aches and I have numbness in pinkie and ring finger and no strengt?

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Left ring finger, pinky, hand, arm, & shoulder suddenly went numb 2 days ago. Cyst in spinal canal, c spine area. Go to ER or wait to see neuro on 30th?

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